The present invention relates to a device for selecting needles in circular knitting machines for hosiery and the like.
Numerous devices are known for the selection of needles in knitting machines and the like. In particular, a device is known which is described in U.S. Pat. No. 4,790,154, granted on Dec. 13, 1988, to the same applicant.
That device comprises a plurality of superimposed selection levers which are individually pivotally connected at an intermediate portion thereof to a support structure and have an end facing the needle cylinder in the zone of the selectors or sub-needles.
The selection levers are individually oscillatable in a plane extending substantially parallel to the extension of the selectors, which pass in front of the selection levers, from an inoperative position, whereat the cited end is located at an intermediate level between the selector butts to avoid interference therewith, to an operative position whereat the cited end is located at the level of the butts to interfere therewith, so as to actuate or not determined selectors which in turn act or do not act on the overlying needles.
Oscillation of the selection levers is effected by actuation levers, which are oscillable in a plane extending substantially parallel to the oscillation plane of the selection levers and which have an end which acts on the opposite part of the selection lever with respect to the selectors.
On each actuation lever act, in an opposed manner, two electromagnets, selectively activatable by a control member which directs the various knitwork workings of the machine.
In order to reduce the overall bulk of the device, even when using a large number of electromagnets, the opposite end of the selection levers is configured as a flat blade, and the end of the actuating lever which engages therewith is bifurcated so as to embrace both sides of the flat blade.
In this way it is possible to arrange the assemblies, constituted by a pair of electromagnets and the relative actuating lever, in a superimposed and laterally offset manner.
That type of device, while permitting a large number of selections, reducing bulk, and increasing actuation speed, has been found to be susceptible, during the course of experimentation, to further modifications directed mainly to the achievement of an even higher actuation speed, so as to increase the potential productivity of the machine and the types of knitwork working which can be performed thereby.